The present invention is directed toward an apparatus and method for providing support for a printed circuit board in a computer system.
There are two critical aspects of effectively connecting a computer component such as a printed circuit board to a computer system. First, a circuit board must be correctly electrically connected and grounded. Second and concurrently, the circuit board must be securely mechanically connected. For the sake of efficiency and the reduction of the number of required assembly parts, electrical grounding connection and mechanical connection are sometimes accomplished with the same assembly parts. A typical printed circuit board that is electrically grounded and mechanically connected within a computer system is a motherboard.
Electrical grounding of a computer chassis and the circuit boards within the chassis is essential to the optimal operation of a computer system. Grounding of an individual circuit board within the computer system allows a ground conductor material within a circuit board to block the electromagnetic interference (EMI) generated by the circuit board from interfering with other circuit boards within the computer system. A ground conductor is formed into a circuit board during circuit board fabrication. The ground conductor is a conductive element that extends across a planar portion of the circuit board. The ground conductor serves to electrically decouple EMI or cross-talk between electric devices on opposing sides of the ground conductor. By including a ground conductor in the circuit boards of a computer system, EMI among circuit boards can be reduced. In order for a ground conductor within a circuit board to be effective, the circuit board must be well connected to a ground source.
A typical ground source for a computer system is the ground supply of a building""s electrical grid. The building""s ground source is usually accessed through a standard wall socket. A computer power cord provides an electrical connection between the ground supply and the computer system. A ground wire of the power cord may be in turn connected to the computer chassis of the computer system. Grounding of the computer circuit boards is accomplished by making an electrical connection between each circuit board and the computer chassis. Alternatively, grounding may be a direct connection to grounding elements on a circuit board rather than through the circuit board connection to the chassis.
Grounding of the entire chassis provides protection to the circuit boards within the chassis. The grounded chassis not only protects a user from shock when touching a chassis energized by a short circuit, but also shields the circuit boards within the grounded chassis from EMI generated by external sources. In addition, the grounded chassis reduces electromagnetic emissions created by the computer circuit boards from interfering with other electrical devices located around the computer system by blocking those emissions.
Generally, mechanical connection of a computer circuit board to a computer chassis is designed to accomplish two goals. First, the connection should be adequately secure to prevent the circuit board from becoming dislodged under anticipated mechanical service loads. Second, the means for making the connection should be easily operable so that the circuit board may be efficiently installed in the computer system upon initial manufacture and so that removal and replacement of the circuit boards for the purpose of maintenance can be accomplished with reduced effort.
A conventional method of attaching computer circuit boards includes the use of screws. A screw can be placed through a hole in the circuit board, and thereby secure the circuit board to a part of a chassis. This type of connection also provides electrical connection when the screw urges a conductive surface of the circuit board onto a conductive part of the chassis. Connection with screws is not, however, considered an optimal method of connection. Screws require relatively large periods of time to install and remove. A loose screw that is misplaced within a computer chassis can cause great damage to the circuit boards by shorting between circuits not intended to make electrical contact. Additionally, if a screw is misdirected by an installer and the screw is forced against a portion of the circuit board, damage to the circuit board may be caused.
An improved device would provide a secure mechanical attachment without the use of screws or other conventional fasteners. Consequently, the tools required to attach and remove screws are fasteners would not be required. Avoidance of screws or fasteners or the tools needed to apply or remove them would significantly enhance the speed with which a circuit board such as a motherboard could be installed or removed from a computer system. An improved device may also provide a grounding path for the circuit board.
An embodiment of the invention is a circuit board support clip with a base having a first end and a second end opposite the first end. The support clip also has a first leg with a coupled end and a distal end. The coupled end of the first leg is coupled to the first end of the base. The first leg is for supporting a circuit board. A second leg has a coupled end and a distal end. The coupled end of the second leg is coupled to the second end of the base. The second leg is for supporting the circuit board. The first leg and the second leg are shaped to exert force on the circuit board in substantially opposite directions when the first leg and the second leg are supporting the circuit board.
Another embodiment of the invention is method of supporting a circuit board on a clip comprising the acts of: aligning two holes in the circuit board with distal ends of two legs of the clip; and pushing the circuit board toward a base of the clip until the legs are deflected to couple the circuit board with notches in the legs to restrict movement of the circuit board along longitudinal axes of the legs.
Yet another embodiment of the invention is a computer system with a chassis, a circuit board coupled to the chassis, and a circuit board support clip for coupling the circuit board to the chassis. The circuit board support clip includes a base having a first end and a second end opposite the first end. The circuit board support clip also includes a first leg having a coupled end and a distal end. The coupled end of the first leg is coupled to the first end of the base. The first leg is for supporting the circuit board. The circuit board support clip also has a second leg with a coupled end and a distal end. The coupled end of the second leg is coupled to the second end of the base. The second leg is for supporting the circuit board. The first leg and the second leg are shaped to exert force on the circuit board in substantially opposite directions when the first leg and the second leg are supporting the circuit board. The computer system also has a power supply coupled to the chassis and electrically connected to said circuit board, a central processing unit electrically connected to the circuit board, and a memory module electrically connected to the circuit board.